• 제목/요약/키워드: Channel forming

검색결과 204건 처리시간 0.022초

충적하천의 하도형성유량 산정과 수리기하특성에 관한 연구 (A Study on the Channel forming Discharge Estimation and the Hydraulic Geometry Characteristics of the Alluvial Stream)

  • 이희철;이은태
    • 한국수자원학회논문집
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    • 제36권5호
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    • pp.823-838
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    • 2003
  • 많은 강과 하천에서 하나의 대표적인 유량이 안정하도 형태를 결정하는데 사용되어 질 수 있다. 이러한 대표적인 하도형성유량은 여러 연구자들의 접근 방식의 차이에 따라 강턱유량, 특정 재현기간유량, 유효유량 등으로 표시된다. 따라서 본 연구에서는 대상유역의 특성인자와 관측자료를 이용하여 하도형성유량을 산정하고, 강턱유량과 수리기하 특성간의 상관관계를 분석하였다. 문막과 서면 수위관측소에서 하도형성유량으로 결정된 강턱유량의 재현기간은 유출량 자료를 빈도분석한 결과, 문막은 1.8년, 서면은 1.5년으로 산정되었으며, 유효유량은 강턱유량에 비해 10배 이상 작게 산정되었다. 강턱유량과 수리기하특성과의 상관관계를 분석한 결과, 유역면적과 강턱유량은 어느 정도 상관성이 있으나 강턱유량과 수리기하간의 상관성은 낮은 것으로 분석되었다.

Structural Design and Characterization of a Channel-forming Peptide

  • Krittanai, Chartchai;Panyim, Sakol
    • BMB Reports
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    • 제37권4호
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    • pp.460-465
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    • 2004
  • A 16-residue polypeptide model with the sequence acetyl-YALSLAATLLKEAASL-OH was derived by rational de novo peptide design. The designed sequence consists of amino acid residues with high propensity to adopt an alpha helical conformation, and sequential order was arranged to produce an amphipathic surface. The designed sequence was chemically synthesized using a solid-phase method and the polypeptide was purified by reverse-phase liquid chromatography. Molecular mass analysis by electro-spray ionization mass spectroscopy confirmed the correct designed sequence. Structural characterization by circular dichroism spectroscopy demonstrated that the peptide adopts the expected alpha helical conformation in 50% acetonitrile solution. Liposome binding assay using Small Unilamellar Vesicle (SUV) showed a marked release of entrapped glucose by interaction between the lipid membrane and the tested peptide. The channel-forming activity of the peptide was revealed by a planar lipid bilayer experiment. An analysis of the conducting current at various applied potentials suggested that the peptide forms a cationic ion channel with an intrinsic conductance of 188 pS. These results demonstrate that a simple rational de novo design can be successfully employed to create short peptides with desired structures and functions.

옴니채널 성향, 조절초점과 고려상표군 형성에 관한 연구 (The Influence of Omni-channel Propensity and Regulatory Focus on Consideration Set Formation)

  • 한상설
    • 산경연구논집
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    • 제10권5호
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    • pp.49-58
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    • 2019
  • Purpose - Consumer behaviors or decision-making process has been changing recently as the consumer environment, including mobile everyday life, has changed. In view of this changing consumer smart environment, this study aims to investigate structural relation about the influence omni-channel propensity and regulatory focus on consideration set formation. Research design, data, and methodology - In order to proceed with this study, we review previous studies and setting hypotheses. The hypothesis was verified through a survey that was conducted for university students with experience in purchasing in less than three months. With reference to previous studies, operational definition was made for the questionnaire design. From 2018 Nov. to 2019 Feb. Survey was conducted on the panel consumers who purchase item within that period. 315 collected survey data were used to verify hypotheses except the data that had incorrect values. This data were used for SPSS/AMOS for confirm hypothesis which developed by researcher. Results - The results of this study are as follows. First, Consumers were considering a more heterogeneous alternatives if they were more omni-channel propensity in the process of forming consideration set. Second, Consumers were more conscious of the price if they were more omni-channel propensity Third, Consumers were considering a more newness alternatives if they were more omni-channel propensity in the process of forming consideration set. Meanwhile, The results of the study on regulatory focus and consideration set relationships are as follows. Consumers were considering a more heterogeneous alternatives if they were more promotion focus tendency in the process of forming consideration set. Second, Prevention focus tendency were more conscious of the price in the process of considering alternatives. Third, Consumers were considering a more newness alternatives if they were more promotion focus tendency. Conclusions - Depending on the changing consumer environment, the omni-channel propensity was shown to influence the formation of the consideration set. Also, Regulatory focus of consumers significantly influence to formation of consideration set. this study also contributes to the development of the theory as well as the practical approach with understanding consumer decision process on smart(mobile) environment.

Design of flat fluorescent lamp(FFL) channel for LCD TV backlight unit by optical simulation

  • Park, J.;Lim, S.
    • 한국정보디스플레이학회:학술대회논문집
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    • 한국정보디스플레이학회 2006년도 6th International Meeting on Information Display
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    • pp.1330-1333
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    • 2006
  • The channel shape of FFL(Flat Fluorescent Lamp) was designed by optical simulation. It was possible to design and manufacture the channel in any shape using glass forming. The best suitable brightness uniformity of 83.7% was achieved.

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IEEE 802.11 메쉬 네트워크에서 채널 다양성과 노드 연결성 향상을 위한 레이트 분할 멀티 채널 프로토콜 (A Rate Separating Multi-Channel Protocol for Improving Channel Diversity and Node Connectivity in IEEE 802.11 Mesh Networks)

  • 김석형;서영주;권동희
    • 한국통신학회논문지
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    • 제35권12A호
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    • pp.1152-1159
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    • 2010
  • 무선 메쉬 네트워크는 무선 링크를 통해 백본 네트워크를 형성하여 사용자에게 인터넷 접근을 제공한다. WMN의 주요 이슈는 네트워크 용량이다. 이를 위해 IEEE 802.11 의 멀티 채널과 멀티 레이트를 활용할 수 있다. 채널은 채널 할당에 따라 노드 연결성 (node connectivity)과 채널 다양성 (channel diversity)을 결정한다. 또한, IEEE 802.11 멀티 레이트 네트워크에서는 RA (Rate Anomaly) 문제가 발생하는데, 이는 낮은 레이트 링크들이 높은 레이트 링크의 성능을 심각히 저하시키는 현상이다. 본 논문에서는 노드 연결성과 채널 다양성을 향상시키고 RA문제를 완화하는 레이트 분할 멀티 채널 (Rate Separating Multi-Channel, RSMC) 프로토콜을 제안한다. RSMC는 트리 기반 WMN를 형성하여 채널 다양성을 증가시키고, 다른 레이트를 사용하는 트리 위의 링크들을 채널로 분리시켜 RA를 줄인다. 또한, 노드 연결성을 증가하기 NC (Network Connectivity) 알고리즘을 사용한다. 시뮬레이션을 통해 RSMC이 기존 멀티 채널 프로토콜보다 총 처리율, 노드 연결성, 채널 다양성 측면에서 향상된 성능을 보임을 입증하였다.

가상안테나를 이용한 스마트 안테나의 성능개선 (Improvement of Smart Antenna System Performance Using virtual antennas)

  • 임채현;문성훈;한동석
    • 대한전자공학회:학술대회논문집
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    • 대한전자공학회 2001년도 하계종합학술대회 논문집(1)
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    • pp.49-52
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    • 2001
  • A virtual antenna system is presented to increase the channel capacity of a smart antenna in cdma2000. Although a smart antenna system can increase channel capacity by forming a beam to a desired user direction, an increase of channel capacity is limited by the number of antenna elements. A virtual antenna is proposed to improve the channel capacity by increasing the degree of freedom. The results show that the proposed system has a larger channel capacity than a conventional smart antenna system for the same number of antenna elements.

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고강도 강판 성형 공정의 스프링백 제어 (Springback Control in the Forming Processes for High-Strength Steel Sheets)

  • 양우열;이승열;금영탁;황진영;윤치상;신철수;조원석
    • 소성∙가공
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    • 제12권8호
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    • pp.718-723
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    • 2003
  • Tn order to develop springback control technology for high-strength steel sheets, several studies have been conducted: dome stretching test, stepped s-rail forming and springback measurement, and optimally shaped initial blank design. First, to find out the formability of TRIP60, dome stretching test was performed. Next, the stepped s-rail die, which was designed to form a channel type panel with large twist and wall curl, was manufactured and used to evaluate the effect of controlling forming variables, such as blank holding force and flange amount on the springback. Furthermore, new measurement method of the springback was introduced to define wall curl and twist in geometrically complex panels. Finally, the optimally shaped initial blank was employed to verify one of the best ways to control the springback in channel type. high-strength sheet panels.

등통로각압축 공정용 저하중 분리형 금형 설계 (Split Die Design for ECAP with Lower Loads)

  • 진영관;강성훈;손일헌;임용택
    • 대한기계학회논문집A
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    • 제32권3호
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    • pp.217-222
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    • 2008
  • Equal channel angular pressing (ECAP) is one of the effective methods to produce bulk-nano materials by accumulating plastic strain into the workpiece without changing its cross-sectional shape in the multi-pass processing. However, the forming load becomes higher for manufacturing large specimens using conventional solid or split dies because of friction, flash formation, and usage of dummy specimen. In the present investigation, better split die was designed to reduce the forming loads and improve the geometrical accuracy of the specimen in the multi-pass ECAP. The new die exit channel was also designed to reduce the friction effect. Experiments with AA1050 specimens with a square cross-section were carried out to examine the design goal using the proposed split dies for routes A and C up to four passes. The numerical forming simulations were used to determine the effective geometry of various die models in the present work.

굽힘과 드로잉에서 성형인자가 탄성복원에 미치는 영향 (Effect of Forming Factor on Springback in U-bended and Drawn Channel)

  • 한영호;송윤준;김형진;정영혁
    • 한국소성가공학회:학술대회논문집
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    • 한국소성가공학회 2002년도 춘계학술대회 논문집
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    • pp.90-93
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    • 2002
  • Assuring required dimensional tolerance after spingback becomes the main concern of sheet-forming die designers when formability is secured through previous tryout. As a part to build a guideline to control springback in automobile frame forming, experiments are carried out to show the effects of process parameters, such as holding force, blank size, and lubrication, on corner angles of channels formed by U-bending or by square-cup drawing and trimming. The results are resented in the viewpoint of evaluating parameters.

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롤 포밍 공법을 이용한 고강도 차체 부품 제작 기술 개발 (Development of Manufacturing Technology for Center Floor Cross Member with Roll Forming Process)

  • 김동규;박상언;조국래;이규현;김광희;이문용
    • 한국소성가공학회:학술대회논문집
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    • 한국소성가공학회 2009년도 추계학술대회 논문집
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    • pp.297-300
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    • 2009
  • The roll forming process is often used to manufacture long, thin-walled products such as a pipe. The final cross-section is a comparatively simple open-channel, a closed tube section or a complex profile with several bends. In recent years, that process is often applied to the bumper beam in the automotive industries. In this study, a optimal Center Floor Cross Member manufacturing technology, model deign and proper roll-pass sequences can be suggested by forming number of roll-pass and bending angle, and also effects of the process parameters on the final shape formed by roll forming defects were evaluated.

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